In general, a plasma display panel (PDP) includes an upper substrate, a lower substrate, and a plurality of barrier ribs which are disposed between the upper substrate and the lower substrate and define a plurality of cells, and each of the cells is filled with a main discharge gas such as neon (Ne), helium (He) or a mixed gas (Ne+He) of neon and helium and an inert gas including a small amount of xenon. When a discharge occurs due to a high-frequency voltage, an inert gas generates vacuum ultraviolet (UV) rays, and the UV rays excite a phosphor layer between the barrier ribs, thereby realizing an image. PDPs are thin and light-weighted and have long been expected to become dominant next-generation display devices.
A conventional PDP includes an upper panel on which images are displayed and a lower substrate which is a predetermined distance apart from the upper panel and is coupled in parallel to the upper substrate. A plurality of sustain electrode pairs, a plurality of black matrices, and a dielectric layer are formed on the upper substrate, and a plurality of address electrodes, a phosphor layer, and a dielectric layer is formed on the lower substrate. Each of the sustain electrode pairs includes a scan electrode and a sustain electrode, and the address electrodes intersect the sustain electrode pairs.
The manufacture of such conventional PDP generally involves manufacturing a glass substrate, manufacturing an upper panel, manufacturing a lower panel, and assembling a PDP. During the manufacture of upper and lower panels, and particularly, during the firing of electrodes, black matrices or a dielectric layer, air bubbles may be generated. In this case, when a voltage is applied, the dielectricity of electrodes may break down due to the concentration of the voltage on portions of the electrodes including air bubbles, thereby damaging an upper or lower panel and eventually reducing the reliability of a plasma display device.